1. Technical Field
The disclosure relates generally to a stand-by management method and management module and computer system using the same, and, more particularly to a stand-by management method and management module and computer system using the same for an S1 or S3 state in ACPI (Advanced Configuration and Power Interface) states.
2. Background
The ACPI (Advanced Configuration and Power Interface) standard is used in conventional computer systems for power saving. The ACPI standard is also used in portable computers such as notebooks for power management. Five ACPI states, such as S0, S1, S3, S4 and S5 states, are commonly utilized in computer systems. Computer systems can normally operate in the normal state (S0 state) and after the computer system is idle for a predetermined period, the computer system enters one of the stand-by states S1 to S5 that offer power saving, wherein the S3 state offers improved power savings over the S1 state, the S4 state offers improved power savings over the S3 state and so on.
In current computer systems, a BIOS (basic input/output system) can inform an OS (operation system) to enter the stand-by state. Users may choose the S1 or S3 state as the stand-by state of the OS by the BIOS setting. In other words, the BIOS may inform the OS to enter the S1 or S3 state. In the S3 state, most power supplies of devices of a computer system will be turned off in the S3 state while power supplies of all of the devices of a computer system will be turned on in the S1 state. Thus, when considering low power consumption, users may choose the S3 state as the stand-by state of the OS. Although the S3 state uses less power than the S1 state, the time required for resuming to a normal working state is longer than that for the S1 state. A display screen unit (e.g. a LCD) is turned off in the S1 or S3 state.
Conventionally, a computer system will automatically enter a predefined stand-by state after the computer system is idle for a predetermined power saving time period. However, when the computer system is in the stand-by state S1 or S3, the display unit will be turned off and thus more time is needed for the computer system to return to the normal state. Meanwhile, if the user requires viewing the screen while the computer system is in the stand-by state, the user may need to issue a resume command manually such as clicking the mouse and wait for the computer system to resume operation from the stand-by state to the normal state, which is inconvenient for users.